Chloramine is becoming more popular for disinfection but transformation of nitrogenous organic compounds during chloramination is largely unclear. This study investigated the transformation of model nitrogenous organic compounds including 4-amino-2-chlorobenzoic acid, adenine, cytosine, and phenylalanine during chloramination with changes of monochloramine dosage, reaction time, and pH. An optimum collision energy-dependent electrospray ionization triple quadrupole mass spectrometry (ESI-tqMS) method capable of differentiating the location of chlorine substitution was used to propose products and pathways. Chloramination of 4-amino-2-chlorobenzoic acid mainly produced two di-chloro and four tri-chloro compounds with all chlorine atoms attached on the unopened benzene ring. Increasing monochloramine dosage led to increases in chlorine substitution to form the di-chloro compounds and then the tri-chloro compounds. The tri-chloro compounds were not stable and likely went through hydrolysis, which resulted in the decreases in their abundances with prolonged reaction time. Changes of pH however did not substantially affect the abundances of these products. Transformation of other model nitrogenous organic compounds during chloramination under the various conditions will also be presented.

Transformation of model nitrogenous organic compounds during chloramination

248th National Meeting (2014)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.